This is a new edition of the New Oxford Thesaurus of English. Fully revised using Oxford's language research programme, it offers more than 600,000 alternative and opposite words, plus a wealth of other features. It is the perfect reference tool to help you expand your vocabulary and write more effectively.
Various is the correct author for any book with multiple unknown authors, and is acceptable for books with multiple known authors, especially if not all are known or the list is very long (over 50).
If an editor is known, however, Various is not necessary. List the name of the editor as the primary author (with role "editor"). Contributing authors' names follow it.
Note: WorldCat is an excellent resource for finding author information and contents of anthologies.
Seems a bit random to put a thesaurus here, but I've decided to put this in my school books shelf, because I spent my entire childhood with my nose buried into a thesaurus while doing coursework. In my English lessons I would be sat next to the bookshelf and it was heaven.